Evening rush commuters spared ahead of 2nd snow wave

Traffic crawls along the Eisenhower Expressway in Chicago as snow builds on the road. (Chuck Berman/Chicago Tribune)

Evening commuters have dodged a major weather bullet, as heavier snowfall isn't expected to fall on Chicago until the overnight hours.

As city and state officials scrambled to keep area roadways clear, officials with the National Weather Service said that a lake-effect snowstorm is expected to dump between 2 to 4 inches of additional snow on Chicago, with more in outlying areas.

About 3.4 inches of snow fell in the city so far, according to meteorologist Nathan Marsili.

The overnight snowfall will continue into Friday afternoon, when the storm's focus moves to northwest Indiana, Marsili said.

Travel times on some expressways were well over an hour above the norm at the peak of the morning rush hour. The storm also canceled more than 500 flights, closed more than 150 schools and caused numerous spin-out accidents.

Chicago's full fleet of 275 trucks were deployed, most of them on side streets during the evening rush hour.

Streets and Sanitation Cmsr. Thomas Byrne said the city will watch the situation before deciding how many trucks to send back into the main streets.

The city is also using 900 cameras around the city to monitor roads conditions.

The lake-effect snow tonight will be accompanied by high winds, causing considerable blowing and drifting snow and reducing visibility to as low as one half mile, with roads covered and slick, the weather service reported.